I need help identifying the year and value of a revolver I got from my grandfather. I was told it was his sidearm in World War II. On the barrel it says "38 S&W Special CTG". The bluing is in very good condition, the gun still fires (although it has not been fired in 20+ years), and to the best of my knowledge, all parts are original. The serial number on the butt is 503109. Below are pictures of both sides of the gun.

5 or 6 chambers in the cylinder? From the photos, it appears to be 5, which would make it a J-frame, most likely a Model 36, and from the sn the production date would be in the 1962 (sn 295000) to 1969 (sn 786544) time frame, with the shape of the thumb piece making it post-1966. All that would also be consistent with the ramped front sight, which is generally indicative of more modern production, and again from the photos (admittedly a bit difficult to tell) it appears to be a 3-screw, which would also be consistent with that time period. If that's the case, however, it should have the model number clearly stamped in the frame cutout, and it's obviously not possible that the gun was carried in WW2 - so I could be totally off base, but that's what it looks like to me.